From 16559ce4f36b9a92f14aa618863b5f485bff66b4 Mon Sep 17 00:00:00 2001
From: Alexander Borisov <alexander.borisov@nginx.com>
Date: Tue, 19 Mar 2019 18:26:44 +0300
Subject: [PATCH] Fixed Math.max() for undefined arguments.

---
 njs/njs_math.c           |  8 +++++++-
 njs/test/njs_unit_test.c | 12 ++++++++++++
 2 files changed, 19 insertions(+), 1 deletion(-)

diff --git a/njs/njs_math.c b/njs/njs_math.c
index 31a8f11b..e96f562e 100644
--- a/njs/njs_math.c
+++ b/njs/njs_math.c
@@ -502,7 +502,11 @@ njs_object_math_max(njs_vm_t *vm, njs_value_t *args, nxt_uint_t nargs,
 
     if (nargs > 1) {
         for (i = 1; i < nargs; i++) {
-            if (!njs_is_numeric(&args[i])) {
+            if (njs_is_undefined(&args[i])) {
+                num = NAN;
+                goto done;
+
+            } else if (!njs_is_numeric(&args[i])) {
                 njs_vm_trap_value(vm, &args[i]);
 
                 return njs_trap(vm, NJS_TRAP_NUMBER_ARG);
@@ -519,6 +523,8 @@ njs_object_math_max(njs_vm_t *vm, njs_value_t *args, nxt_uint_t nargs,
         num = -INFINITY;
     }
 
+done:
+
     njs_value_number_set(&vm->retval, num);
 
     return NXT_OK;
diff --git a/njs/test/njs_unit_test.c b/njs/test/njs_unit_test.c
index 8edae9c0..e11a5054 100644
--- a/njs/test/njs_unit_test.c
+++ b/njs/test/njs_unit_test.c
@@ -10028,6 +10028,18 @@ static njs_unit_test_t  njs_test[] =
     { nxt_string("Math.max('1', '2', '5')"),
       nxt_string("5") },
 
+    { nxt_string("Math.max(5, {valueOf: function () {return 10}}, 6)"),
+      nxt_string("10") },
+
+    { nxt_string("Math.max(5, {valueOf: function () {return 10}}, 20)"),
+      nxt_string("20") },
+
+    { nxt_string("Math.max(5, undefined, 20)"),
+      nxt_string("NaN") },
+
+    { nxt_string("Math.max(-10, null, -30)"),
+      nxt_string("0") },
+
     { nxt_string("Math.min()"),
       nxt_string("Infinity") },
 
-- 
2.47.3